Chemotherapy for breast cancer uses powerful drugs to target and destroy breast cancer cells. Chemotherapy for breast cancer frequently is used with other treatments, such as surgery, radiation or hormonal therapy. Combining chemotherapy for breast cancer with other treatments may increase the chance of a cure or decrease the risk of the cancer returning.

If the cancer has recurred or spread, chemotherapy for breast cancer may control the cancer to help you live longer. Or it can help ease symptoms the cancer is causing.

But chemotherapy for breast cancer also carries a risk of side effects — some temporary and mild, others more serious or permanent. Your doctor can help you decide whether chemotherapy for breast cancer is a good choice for you.

Chemotherapy for breast cancer may be given in the following situations:

Chemotherapy after surgery for early breast cancer

After surgical removal of a tumor from a breast, your doctor may recommend chemotherapy to destroy any undetected cancer cells and to reduce your risk of the cancer recurring. This is known as adjuvant chemotherapy.

Your doctor may recommend adjuvant chemotherapy if you have a high risk of the cancer recurring or spreading to other parts of your body (metastasizing), even if there is no evidence of cancer after surgery. You may be at higher risk of metastasis if cancer cells are found in lymph nodes near the breast with the tumor.

It's important to talk to your doctor about how much the chemotherapy will reduce your chance of the cancer coming back, and whether this decrease in risk is worth the side effects of the chemotherapy. Also discuss with your doctor other alternatives, such as hormone-blocking therapy, that might be effective in your situation.

Chemotherapy before surgery for early breast cancer

Some women with breast cancer receive chemotherapy before surgery (neoadjuvant therapy), generally to shrink large tumors and allow the surgeon the best chance of removing the tumor completely. In some cases, neoadjuvant therapy allows the surgeon to remove only the tumor, rather than the entire breast. This can also decrease the chance the cancer will return at a later date.

Chemotherapy as the primary treatment for advanced breast cancer

If breast cancer has spread to other parts of your body, and surgery isn't an option, chemotherapy can be used as the primary treatment. It may also be used in conjunction with hormone therapy or targeted therapy, depending on the type of breast cancer you have.

The main goal of chemotherapy for advanced breast cancer is generally to improve quality and length of life rather than to cure the disease.

Chemotherapy's side effects are different for everyone, due to differences among drugs and dosages and to the body's unique reaction to these medicines. Most side effects are temporary and subside once treatment is finished. But in some cases, chemotherapy can have long-term or even permanent effects.

Short-term side effects

In the process of killing cancer cells, chemotherapy drugs can also damage other rapidly dividing healthy cells, such as those in the hair follicles, bone marrow and digestive tract. The results may include:

Hair loss

Loss of appetite

Nausea and vomiting

Diarrhea

Mouth sores

Fatigue (due to fewer red blood cells)

Increased risk of bruising or bleeding (due to fewer blood platelet cells that help blood clot)

There are drugs to help reduce nausea and vomiting caused by chemotherapy. Also, doctors can sometimes adjust the dose or schedule of the chemotherapy drugs to minimize side effects.

If chemotherapy damages your infection-fighting blood cells, a doctor may adjust your doses of chemotherapy or add medications that help your bone marrow to recover more quickly. Most side effects don't last long.

Long-term side effects

Infertility. One possible side effect that may not go away is infertility. Some anti-cancer drugs damage ovaries.

This may cause menopause symptoms, such as hot flashes and vaginal dryness. Menstrual periods may become irregular or stop (amenorrhea). If ovulation ceases, pregnancy becomes impossible.

If you continue to menstruate, you may still be able to get pregnant, even during treatment. But because the effects of chemotherapy are dangerous to the fetus, talk with your doctor about birth control options before treatment begins.

Nerve damage (neuropathy). Several chemotherapy drugs can affect nerve endings in your hands and feet, leading to numbness, pain, burning or tingling, sensitivity to cold or heat, or weakness in your extremities. These side effects often go away after treatment is finished, but in some cases, they may be long lasting.

Osteoporosis. Women who experience menopause early because of chemotherapy may have a higher risk of the bone-thinning condition osteoporosis. It's generally recommended that these women have periodic bone density tests and, possibly, treatments to prevent bone loss.

Cognitive function. "Chemo brain," "chemo fog" and "chemo memory" are terms used to describe little-understood short-term memory and concentration problems that may occur after chemotherapy. In most cases, these problems go away within a few years.

Heart damage. When used for a long time and in high doses, some drugs — such as epirubicin (Ellence), trastuzumab (Herceptin) and others — can cause permanent heart damage.

Leukemia. Rarely, chemotherapy for breast cancer triggers a secondary cancer, such as cancer of the blood cells (leukemia).

Other side effects

Feelings of fear, sadness and isolation can compound the physical side effects of chemotherapy, both during and after treatment. In fact, some women are unexpectedly sad at the conclusion of treatment.

During chemotherapy, women with breast cancer have regular contact with and support from oncologists and nurses. Everyone involved is working toward the same goal — completion of treatment with the best possible outcome. When it's over, some women feel as if they're alone, with no one to help them return to normal life or deal with fears of breast cancer recurrence.

It may help to talk with someone who has been in the same situation. Connect with others via a cancer-survivor hot line, support group or online community.

You and your doctor may go through several steps in preparation for chemotherapy.

Assess the potential benefit of chemotherapy

Your doctor considers a number of factors to determine whether and what kind of chemotherapy would benefit you. The higher your risk of recurrence or metastasis, the more likely chemotherapy will be of benefit. In some cases, characteristics of the breast cancer itself may suggest other more beneficial treatments.

Tumor size and grade. The more advanced the tumor, the more likely chemotherapy may be useful in destroying stray cancer cells.

Lymph node status. Breast cancer cells found in your lymph nodes during or before surgery signal a higher risk of metastasis. Your doctor is likely to recommend chemotherapy.

Age. Some studies suggest that breast cancer that occurs at a young age is more aggressive than breast cancer that develops later in life. So doctors may opt for adjuvant chemotherapy when treating younger women to decrease the chances of the cancer spreading.

Previous treatments. Whether you've had chemotherapy before may affect your current treatment regimen.

Chronic health conditions. Certain health problems, such as heart disease or diabetes, may affect the chemotherapy drugs used to treat you.

Hormonal status. If your breast cancer is sensitive to the hormones estrogen and progesterone, hormone therapy — with drugs such as tamoxifen (Soltamox), fulvestrant (Faslodex) or aromatase inhibitors (Arimidex, Femara, Aromasin) — may be a better option for post-surgical adjuvant therapy. Or they may be considered in addition to chemotherapy.

Genetic profile. For certain types of breast cancer, some doctors may do genetic testing of tumor tissue to learn genetic patterns that may help predict the risk of recurrence. Some still consider these tests experimental.

Take steps to improve your overall health

Because chemotherapy can affect fast-growing healthy cells, such as your white blood cells, platelets and red blood cells, it helps to be as healthy as possible before you begin treatment, to minimize its side effects. Your doctor may recommend that you take the following steps to optimize your overall health:

Get plenty of rest.

Eat a balanced diet rich in fruits, vegetables and whole grains.

Minimize stress.

Avoid infections, such as the common cold and the flu. Talk to your doctor about recommended vaccinations, including annual flu vaccines.

See your dentist for any signs of infection in your teeth or gums.

Undergo blood tests to check your liver function and tests to check your heart. If there are any problems, your doctor may delay your treatment or select a chemotherapy drug and dosage that are safer for you.

Plan ahead for side effects

Ask your doctor what side effects you can expect during and after chemotherapy and prepare. For instance, if your chemotherapy treatment will cause infertility, you may wish to store sperm or fertilized eggs for future use. If your chemotherapy will cause hair loss, consider a wig or head covering.

Make arrangements for help at home and at work

Most chemotherapy treatments are given in an outpatient clinic, which means most people are able to continue working and doing their usual activities during chemotherapy. Your doctor can tell you how much the chemotherapy will affect your usual activities, but it's difficult to predict just how you'll feel.

Prepare by asking for time off work or help around the house for the first few days after treatment. If you'll be in the hospital during chemotherapy treatment, arrange to take time off work, and find someone to take care of your children, pets or home.

Tell your doctor about any drugs or supplements you're taking

Be sure your doctor knows about any medications or supplements you're taking, including any herbal supplements, vitamins or over-the-counter drugs. These may affect the way the chemotherapy drugs work. Your doctor may suggest alternative medications or that you not take the medications or supplements for a period before or after a chemo session.

The day of treatment

Your doctor or nurse will let you know what you can and can't eat or drink on the day of your chemotherapy session. It may help to take a family member or friend with you to the treatment session, for support and companionship.

Timing and frequency of chemotherapy sessions

Chemotherapy for breast cancer is given in cycles. The cycle for chemotherapy can vary from once a week to once every three weeks.

Typically, you'll undergo chemotherapy treatments for three to four months, but your doctor will adjust the timing to your circumstances. If you have advanced breast cancer, treatment may continue beyond six months.

Common drug combinations

There's an array of chemotherapy drugs available. Because each person is different, doctors tailor certain types and doses of medications (regimens) — often a combination of chemotherapy drugs — to the type of breast cancer and the person's medical history.

Where chemotherapy is given

Most breast cancer chemotherapy sessions take place at one of these places: a doctor's office or an outpatient unit in a hospital or clinic.

How chemotherapy is given

Chemotherapy drugs can be given in a variety of ways, including pills you take at home. Most often they're injected into a vein (IV). This can be done through:

An IV needle and tube (catheter) in your hand or wrist.

A catheter port implanted in your chest before beginning chemotherapy. This port stays in place for the duration of your chemotherapy treatment and eliminates the need to find a suitable vein at each treatment session.

A typical chemotherapy session

Not all chemotherapy sessions are alike, but a session might follow this order:

You receive medications to prevent side effects such as nausea, anxiety or inflammation.

You receive the chemotherapy drugs. This may take up to several hours.

After a chemotherapy session

Following a chemotherapy session, you may:

Have your catheter removed.

Have your vital signs checked.

Review side effects with your health care provider.

Receive prescriptions for medications you can take at home to help with side effects.

Be advised to drink a lot of fluids.

Receive instructions on proper handling of bodily fluids, such as urine, stool, vomit, semen and vaginal secretions, as these may contain some of the chemotherapy drugs for the next 48 hours. This may simply involve flushing the toilet twice after use.

Some people feel fine after a chemotherapy session and can return to their schedules, but others may feel side effects more quickly. You may want to arrange for someone to drive you home afterward, at least for the first few sessions, until you see how you feel.

During the course of chemotherapy

After a few sessions, you may be able to predict more accurately when you'll feel fine and when you may need to cut back on activities. Marking your calendar or keeping a journal may help you track your general response to chemotherapy sessions and help you plan events accordingly.

Following your treatment plan closely is the best way to get the most benefit from your chemotherapy. If side effects become too bothersome, discuss them with your doctor. He or she may be able to adjust the dose or type of chemotherapy medication you're receiving or prescribe other medications to help minimize side effects.

After you complete your chemotherapy treatment, your doctor will schedule follow-up visits — usually every four to six months at first and then less frequently the longer you remain cancer-free. This is to monitor you for long-term side effects and to check for recurrence of the breast cancer. Tests and procedures during follow-up care include:

Asking you how you feel, including any new symptoms or physical problems you have

Physical exam, including breast exam

Yearly mammogram

Bone density testing

Tests such as tumor marker tests, liver function tests, bone scans and chest X-rays generally aren't recommended unless there is a specific need. Additional imaging tests are typically needed only when a recurrence is suspected or new symptoms or physical exam findings warrant.

Chemotherapy principles: An in-depth discussion of the techniques and its role in treatment. American Cancer Society. http://www.cancer.org/treatment/treatmentsandsideeffects/treatmenttypes/chemotherapy/index. Accessed Aug. 21, 2013.

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